1. Field of the Invention
The present invention relates to a plasma display apparatus having a plasma display panel.
2. Description of the Related Art
Plasma display apparatuses having a plasma display panel (referred to as “PDP” hereinafter) are marketed as thin-type, large-screen display devices. In the PDP, discharge cells corresponding to pixels are arranged in a matrix shape. The PDP implements an image display by using the phenomenon of light emission in accordance with discharge that is induced in each of the discharge cells. Therefore, the discharge voltage of discharge cells decreases as a result of long-term usage and the PDP tends to produce erroneous discharge. To deal with this problem, some display apparatus control a discharge-sustaining voltage that is applied to the discharge cells in accordance with the PDP usage time. One of such apparatus is disclosed in Japanese Patent Application Kokai (Laid Open) No. 9-138668. In this display apparatus, by referencing information indicating the predicted transition of the discharge-sustaining voltage corresponding with the usage time (see FIG. 6 of Japanese Patent Application Kokai No. 9-138668), an output voltage of a power supply circuit is controlled such that the discharge-sustaining voltage has an appropriate value that reflects the apparatus usage time.
However, the output voltage control of such a power supply circuit cannot adequately suppress image quality degradation caused by long-term usage.
Further, there is another problem. When the temperature of the environment in which the plasma display apparatus is used drops, the discharge cells of the PDP discharge erroneously and the display quality drops. To cope with this problem, some plasma display apparatus heat the PDP when the temperature of the PDP is low. One of such apparatus is disclosed in Japanese Patent Application Kokai No. 9-6283.
However, with such a method, a heater for uniformly heating the whole of the PDP must be mounted and the structure of the display apparatus becomes complicated.